WO2014075811A1

WO2014075811A1 - Prosthetic liner

Info

Publication number: WO2014075811A1
Application number: PCT/EP2013/003459
Authority: WO
Inventors: Lüder MOSLER; Kai BUSSIEK
Original assignee: Otto Bock Healthcare Gmbh
Priority date: 2012-11-19
Filing date: 2013-11-16
Publication date: 2014-05-22
Also published as: US20150297369A1; DE102012022484B4; DE102012022484A1

Abstract

The invention relates to a prosthetic liner for forming an interface between a prosthesis socket (5) and a residuum to be accommodated in said prosthesis socket (5), the prosthetic liner (1) having a proximal region (2) with a proximal end (21) and a distal region (3) with a distal end (31) and being provided with a closed-cross section with a proximal opening (22) through which the residuum in inserted into the prosthetic liner (1), wherein the internal contour has at least on one lateral side (19) of the prosthetic liner (1) a greater pitch from distal to proximal in the proximal region (2) than in the distal region (3).

Description

title

Prosthesis liner description

The invention relates to a prosthetic liner for forming an interface between a prosthesis socket and a stump to be received in the prosthesis socket, the prosthetic liner having a proximal portion with a proximal end and a distal portion with a distal end and having a closed cross-section with a proximal opening for insertion provided the stump in the prosthetic liner.

For the prosthetic care of patients, it is necessary to provide a safe and reliable assignment and connection of the prosthetic device to the patient. Prosthetic devices have for this purpose a stable prosthesis shaft, which is more or less exactly replicated to the contour of the stump. For this purpose, it is necessary to provide on a model of the stump or based on computer data as closely as possible appropriate shaft.

Instead of a direct connection of the prosthesis stem to the stump sees an alternative technology that on the stump a liner made of an elastic material is applied, for example silicone. The liner is rolled up onto the stump and serves to compress and protect the soft tissue of the stump. The inside, ie the inner surface of the liner facing the stump, of the liner can be designed to be adhesive. A communicating holding system holds the

Butt-liner combination in the prosthesis stem, for example by a negative pressure. It is also possible and provided that at the distal end of the liner locking bolts are provided, via which a mechanical locking of the liner can be done on the prosthesis stem.

A multilayer prosthetic liner is known from US 2009/0240344 A1. The liner has a circular cross-section perpendicular to the longitudinal extent and is closed and dome-shaped at the distal end, the liner wall extending rectilinearly and conically widening from the distal end. Such a liner is relatively easy to produce in large quantities.

The problem with the use of such a liner is that there is often a lack of adhesion of the liner to the stump on the lateral side.

The object of the present invention is therefore to provide a prosthetic liner which, with good adhesion to the patient, at the same time has a sufficiently high durability and moreover requires no individual preparation.

According to the invention this object is achieved by a prosthetic liner with the features of the main claim. Advantageous embodiments and further developments of the invention are disclosed in the subclaims, the description and the figures. The prosthesis liner according to the invention for forming an interface between a prosthesis socket and a stump to be received in the prosthesis socket, wherein the prosthetic liner has a proximal portion with a proximal end and a distal portion with a distal end and with a closed cross-section with a proximal opening for insertion of the stump in the Prosthesis liner is provided, provides that the inner contour at least on a lateral side of the prosthetic liner from distal to proximal in the proximal region has a greater slope than in the distal region. Whereas in the case of a cylindrical embodiment of a prosthetic liner, there is the danger, at least in the proximal region, that tearing occurs on the medial side and a poor fit on the lateral side occurs in a conical embodiment of a liner, this is due to the inventive design of the prosthetic liner both on the medial side as well as on the lateral side a good adhesion with simultaneous durability of the liner in the proximal area given. The increasing slope or curvature in the direction of the stump from the distal end to the proximal end has the advantage that on the lateral side of the body contour subsequent inner and thus outer contour is formed, especially in the region of the hip joint in prosthesis liners for thigh stumps. The different gradients in the distal and proximal regions are given in particular even in the non-applied state. It is sufficient if, in the proximal region, only one region has a greater slope than the distal region, so as to bring about a curvature and orientation in the direction of the stump. The greater slope or curvature toward the stump need not be over the entire proximal region, in particular, the slope or curvature in the proximal region need not increase, it is sufficient if the slope or curvature or orientation towards the stump in the non-applied state is greater than in the distal area. The slope is the ratio of the difference of the Y-values to the assigned differential. The X values are considered in the course of the contour in a Cartesian coordinate system. The slope of the contour is zero when the tangent to the contour is horizontal, wherein the Y-axis substantially corresponds to the longitudinal extent of the liner and is oriented from proximal to distal. The greater the slope, the more the course of the contour approaches the vertical. A curvature of the contour beyond the perpendicular in the direction of the stump, that is to say into the stump receiving space formed by the liner, is considered to be an increasing curvature when viewing the curvature from distal to proximal. The greater slope is at the same time a greater curvature towards the stump, starting from the distal end of the liner and towards the proximal end.

In the distal region of the prosthetic liner may have a conical or parabolic inner and / or outer contour, so after the cap-like end have a substantially uniform slope at a conical contour, which then arched in the proximal region in an increasing pitch or cylindrical inner contour and thus usually also outer contour passes. It is also possible that a parabolic contour is already present in the distal region, so that there is a change in the gradient extending over the entire distal region.

In the proximal region, a cylindrical, ie substantially straight-walled or parabolically curved inner contour may be present, so that the increase in pitch from the distal region also continues into the proximal region and may also have a curvature in the direction of the stump beyond the vertical.

The distal region, viewed from the distal end, can account for over 30% to 75% of the total length of the prosthetic liner. Below the total length, the maximum length of the prosthetic liner is of the distal len end to understand the proximal end. There is the possibility that the prosthetic liner runs obliquely to the longitudinal extent at its proximal end, which is to be expected in particular for liners for thigh stumps, since the medial side should extend only to the perineum, while the lateral side should extend as high as possible to the hip, to allow sufficient support for the prosthesis stem.

The prosthetic liner may be formed at least in the distal region multi-layered and made of different materials. Preferably, an inner layer of silicone and an outer layer of polyurethane are provided, since silicone has a good skin compatibility and polyurethane can be achieved as an outer layer good pressure distribution and wear resistance. The silicone allows a very good adhesion of the prosthetic liner to the stump with good skin compatibility, the polyurethane layer on the outside of the prosthesis liner allows adaptation to the prosthesis stem. In principle, it is also possible that a different material pairing is used, for example with silicone on the outside and a copolymer on the inside or vice versa.

A textile reinforcement may be provided on or in the prosthetic liner in order to be able to provide increased shape and volume stability. The textile reinforcement may extend over the entire liner, it is also provided that the textile reinforcement is only partially arranged in the prosthetic liner, for example only in the distal region or in the proximal region. The textile reinforcement may be embedded in a layer of the prosthetic liner, interposed between two layers, for example an inner layer and an outer layer of different materials, and completely covered by these layers or arranged on a surface of the prosthesis liner. For example, the arrangement on the outside of the prosthesis Ners be made to achieve an optimized material pairing with a corresponding coating on the inside of the prosthesis stem.

From the distal end to the proximal end of the prosthesis liner, a discontinuous change in elevation may be present in order to be able to achieve an adaptation of the liner to the respective stump that is as contour-appropriate as possible. The discontinuous increase involves incrementing the slope from the distal region to the proximal region in a stepwise fashion, with the slope increasing from distal to proximal and transitioning to an inner curve. There is also the possibility of increasing the slope from distal to proximal between the discontinuous areas.

The liner is preferably formed closed at the distal end, so that the distal end of the stump is covered by the liner material.

In order to increase the wearing comfort of the liner, an outer curvature can be provided at the proximal end on the medial side, so that the upper, that is proximal, edge in the medial area conforms to the perineum through the outer curvature. The curvature at the proximal edge can also be formed circumferentially.

The prosthetic liner may be formed shorter on the medial side than on the lateral side to achieve a proximally higher coverage on the lateral side, so that in conjunction with the curvature toward the body, there is increased curvature in the direction the body or stump can be achieved over the entire length of the prosthesis liner a good all-round investment in the stump.

The prosthetic liner is preferably rotationally symmetrical to its Longitudinal axis formed, at least on the outside, and consists of an elastic material, so that a slight adjustment of the prosthetic liner can be made to the approximately rotationally symmetric stump. The rotationally symmetrical design of the prosthetic liner allows a simple, cost-effective and rapid production and easy adaptation to prefabricated prosthesis stems. There is the possibility that the inner contour of the prosthetic liner has, at least on the lateral side, a course deviating from the contour of the medial side, for example in order to enable an improved abutment with the stump. The prosthetic liners are preferably manufactured in standard sizes whose length is sufficient for all conceivable buttress restorations. The variation in size relates primarily to the diameter or circumference of the prosthetic liner, and optionally the curvature or slope of the contour. In order to adapt the prefabricated prosthetic liner to the respective patient, it is intended to shorten it in length and to cut the proximal edge in such a way that it meets the needs of the patient, ie is shortened in particular in the medial area and left as long as possible in the lateral area. The prosthesis liner according to the invention is therefore designed as a prefabricated standard liner that does not have to be individually adapted to the respective outer contour of a stump, but rather a liner can be selected from a limited number of models and sizes and adapted to the patient by simple modifications.

In a variant of the invention, a padding or thickening is provided at the distal region of the prosthetic liner in order to achieve improved protection of the stump against pressure loads. The Aufpolsterrung or thickening may be formed on the outside of the prosthetic liner by a material is fixed to an outer layer of a prefabricated standard liner, for example by sticking or cohesive fastening by crosslinking uncrosslinked polymers. It is also possible, the material thickening in one piece with the To form prosthesis liner, so directly with mold, for example by the shape design when pouring or dipping the liner. The padding or material thickening is arranged in particular on the lateral side of the prosthetic liner, this orientation being present in the applied state of the liner.

Embodiments of the invention will be explained in more detail with reference to the accompanying figures. Like reference numerals show like components. Show it:

Figure 1 - a schematic sectional view of a prosthesis socket with a liner;

Figure 2 - a liner in a sectional view; such as

Figure 3 - a variant of the prosthetic liner.

FIG. 1 is a schematic sectional view of a prosthesis shaft 5 made of a dimensionally stable material. The prosthesis socket 5 has a substantially tubular structure and has an inner contour which is approximated to the outer contour of a dull, for example a thigh stump, not shown. To achieve sufficient volume stability, the prosthesis shaft 5 is designed to be closed in the circumferential direction and can have a through hole at its distal end 51, through which, for example, a locking bolt can be passed. At the distal end 51 further prosthesis components can be arranged, for example an adapter for receiving joint devices or in the case of leg prostheses a lower leg tube and a prosthetic foot. At the proximal end of the prosthesis shaft 5 opposite the distal end 51, an insertion opening is provided, through which the stump, not shown, can be inserted. In the illustrated embodiment, a prosthetic liner 1 is disposed within the prosthesis socket 5. There is no free space between the outer contour of the prosthetic liner 1 and the inner contour of the prosthesis socket 5. In the applied state of both the prosthetic liner 1 and the prosthesis shaft 5, the outer contour of the prosthetic liner 1 on the inner contour of the prosthesis stem 5 as possible over the entire surface. In the applied state, the prosthetic liner 1 forms the interface between the stump and the prosthesis shaft 5.

The prosthesis liner 1 arranged within the prosthesis socket 5 is constructed in the illustrated embodiment as a single-layer prosthesis liner 1, which may be constructed from a silicone, a copolymer or polyurethane. It is likewise possible to provide a multilayer prosthetic liner 1 which has at least one inner layer and one outer layer made of different materials, such as silicone and polyurethane or a copolymer, optionally with an intermediate layer and / or an insert of another plastic or a textile or fiber material. The prosthetic liner 1 has a proximal end 21 and a distal end 31. The distal end 31 is formed closed in the embodiment, so that a cap-like structure at the distal end of the prosthetic liner 1 results. At the proximal end 21 of the prosthetic liner 1, an opening 22 for insertion of a stump is formed.

In the variant of the invention according to FIG. 1, the prosthesis shaft 5 and the prosthetic liner 1 have a shorter length on the medial side 18 than on the lateral side 19. The sectional contour along the longitudinal extension provides in the exemplary embodiment illustrated two different regions, namely a proximal region 2 and a distal region 3. The proximal region 2, which extends from the upper, proximal edge 21 of the prosthetic liner 1 in the direction of its distal end 31, is substantially cylindrical. The slope of the con- in the proximal region 2 is thus substantially constant, whereas the inner contour of the prosthetic liner 1 curves in the distal region. When viewed from the distal end 31 of the prosthetic liner 1, the inner contour initially has no gradient, since the tangent to the distal end 31 extends horizontally. In the further course from distal to proximal, the gradient increases within the distal region 3, until an at least cylindrical inner contour is present in the transition to the proximal region 2. It is also envisaged that the inner contour of the prosthetic liner 1 curves further in the direction of the stump in order to allow improved adhesion of the liner, in particular on the lateral side 19. An end region with an outer curvature can adjoin the proximal end of the proximal region 2. To increase the wearing comfort of the proximal region 2 on the lateral side 19 is greater than on the medial side 18. In addition, on the medial side 18 and on the lateral side 19 at the upper edge of the prosthetic liner 1 and the prosthesis stem 5, an outer curvature 23, 53 are arranged so that this can create on the medial side 8 in an embodiment as a thigh bone to the perineum, whereby the comfort is also increased.

The prosthesis liner 1 arranged within the prosthesis socket 5 has a rotationally symmetrical structure over the longitudinal extent, at least up to the proximal end of the medial proximal region 2.

FIG. 2 shows the prosthetic liner 1 in a single representation. The prosthetic liner 1 has an outer layer 11 and an inner layer 12, which is fixed to the outer layer 11. Both layers 11, 12 are permanently connected to each other. The inner layer 12 is preferably made of silicone or a silicone material, while the outer layer 11 consists of a copolymer, possibly of polyurethane. Between the outer layer 11 and the inner layer 12, a textile reinforcement 4 is arranged, which is completely embedded in the prosthetic liner 1, so on the outside and the inside is completely covered and only possibly reaches the surface at the proximal end. The textile reinforcement 4 has a substantially cylindrical construction and, in the exemplary embodiment shown, is arranged in a proximal section of the prosthesis liner 1. In principle, it is also possible for the textile reinforcement 4 to be arranged over the entire length of the prosthesis liner 1, and it is also possible for a plurality of independent textile reinforcements 4 to be arranged and embedded within the prosthesis liner 1. The textile reinforcements 4 may have different elasticities, so that different degrees of expansion can be set with the same load over the length of the prosthetic liner 1. In principle, it is possible and provided that textile reinforcements 4 can also be arranged in single-layer prosthesis liners 1.

The prosthetic liner may also basically have a matrix which prevents or minimizes elongation in the longitudinal direction and allows expansion in the circumferential direction. This makes it possible to realize an anisotropic expansion behavior for the prosthetic liner. The matrix may be arranged as a tissue or other insert in or on the prosthetic liner, preferably in the distal region of the prosthetic liner. The matrix, insert or reinforcement prevents or minimizes the so-called milking effect which can occur in the case of a distal locking of the prosthesis liner on the prosthesis shaft by alternating stretching in the direction of the longitudinal extension of the prosthesis liner.

To apply the prosthetic liner 1, the prosthetic liner is first wound from the proximal end, the distal end 31 is placed with the inner layer 12 on the prosthesis stump and then the prosthetic liner 1 is rolled over the stump, so that the inner layer 12 rests on the stump and this over the entire surface covered. The outer layer 11 serves to provide a large-area and advantageously adhesive contact with the inner surface of the in the figure 2 Denture shaft 5, not shown.

The prosthetic liner 1 has a rotationally symmetrical construction along its longitudinal extension, that is to say from the distal end 31 to the proximal end 21, ie it has essentially a circular cross-section perpendicular to the longitudinal extent, at least on the outer side.

A distal region 3, which extends as far as the distal end 31 of the prosthesis liner 1, adjoins the proximal region 2 in the direction of the distal end 13. Starting from the distal tip, where the slope of the contour is zero, the slope of the contour of the outside and the inside of the prosthetic liner 2 increases continuously to the proximal region 2, so that the distal region 3 has a substantially parabolic inner contour. The increase in the slope is the same both on the medial side 18 and on the lateral side 19, so that a symmetrical configuration of the prosthetic liner 1 results. This makes it possible, for fitting the prosthetic liner 1 to the patient, to apply the prosthetic liner 1 without paying any attention to a particular orientation relative to the stump.

Due to the configuration of the prosthetic liner 1 with a contour which has a greater slope in the proximal region 2 than on the distal side 3 in the distal region 3, it is ensured that a particularly good adhesion to the stump exists at the upper edge of the prosthetic liner 1. The bias caused by the concave inward by the shape of the liner 1 ensures that no space is created between the stump and the liner. In the proximal region 2, a negative slope can also occur. In particular, in the case of the beveled variant according to FIG. 1, it is avoided that an excessive tension is built up on the medial side 18, which leads to cracks in the liner material. After fitting the prosthetic liner 1 to the necessary length, the desired curvature is at least at the late ralseite 19 inside. Usually, a limited number of lengths and diameters are sufficient in order to be able to supply the usually occurring stump shapes.

On the lateral outer side of the prosthetic liner 1, a padding 20 is provided in the distal region 3, which extends from the distal end 3 of the prosthetic liner 1 beyond the middle of the distal region 3 in the direction of the proximal region 2. The upholstery 20 in the illustrated embodiment is arranged only on the lateral side 19, so that the rotational symmetry is no longer present. The initially rotationally symmetrical prosthetic liner 1 with the inner layer 12 and the outer layer 11 was subsequently provided with the padding 20, which was attached to the outside of the outer layer 11, for example glued or permanently attached by crosslinking with the material of the outer layer 1. The material of the upholstery 20 may be different from the material of the outer layer 11. As an alternative to the illustrated embodiment, it is also possible that the padding 20 is disposed rotationally symmetrical about the entire outer surface of at least the distal region 3. It is also possible to design the upholstery 20 from the material of the outer layer 11 and to form the outer layer 11 in one piece, so that the upholstery 20 is already produced during the production of the outer layer 1. The padding 20 in the lateral area of the femur makes artificial soft-tissue padding possible, in particular in the case of mature atrophied stumps with little soft-tissue coverage. The padding also allows for an abduction position of the femur, an additional positioning of the femur by this inward, ie in the medial direction, moved or pushed. This supports the positioning of the femur in the prosthetic socket. In the embodiment of the prosthetic liner 1 as a thigh bone, the padding 20 thus causes a soft tissue padding in the region of the femur and a positioning of the femur, and the stresses on the thigh bone are reduced. Ringert.

The arrangement of the padding 20 at the distal end 31 of the prosthetic liner 1 results in a material thickening, so that an improved cushioning effect is achieved with an axial load, that is, a load along the longitudinal extent of the prosthetic liner 1.

FIG. 3 shows a variant of the invention in which the padding 20 is arranged exclusively on the lateral side 19 of the prosthetic liner. Thus, only a relatively small, located on the lateral side 19 region of the distal region 3 is provided with the padding 20 in order to effect specifically at those points a thickening of the material, which must be specially protected. Only when applying the liner is to pay attention to a precise positioning of the padding 20 at the desired position, preferably on the lateral side of the stump.

The prosthetic liner 1 according to the embodiment of FIG. 3 has no textile insert 4 or other reinforcement in the intermediate region between the inner layer 12 and the outer layer 11. In both embodiments of the liner 1 according to FIGS. 2 and 3, the proximal region 2 extends up to the proximal end 21, the inner contour having a greater pitch than the contour of the distal region 3 due to the cylindrical configuration. In principle it is also possible that an additional curvature in the direction of the not shown stump or the center axis of the prosthetic liner 1 may take place, zumin- ^'least on the lateral side 19, an optimized attachment and installation of the prosthetic liner 1 to the outer contour of the stump to cause.

In the embodiments of the figures, the distal region 3 is conical or parabolic and extends over more than half the total length of the liner. The proximal region 2 merges into a cylindrical or approximately cylindrical shape and forms the remaining length for the prosthetic liner 1 out. Due to the proximal widening contour of the prosthetic liner 1 on the medial side 18, the formation of cracks in the medial edge region is prevented. The prosthetic liner 1 is formed in the illustrated embodiments distally closed and has a closed circumference, so that it can also be used as a liner in Saugschäften. Furthermore, the liner can be used in prosthetic stems, which are used as a pure volume shaft without bony Tuberabstützung, whereby the distal portion of the stump must perform an increased support function. Therefore, it is advantageous if a soft, adhesive inner layer 12 of silicone and a stable and adherent outer layer 11 of polyurethane or other copolymer are present. In this case, the distal region 3 can have a greater wall thickness than the proximal region 2, in particular the distal end 31 of the prosthetic liner 1 can have an increased material thickness, in particular the inner layer 12.

The cross-section of the prosthetic liner is designed to be closed perpendicular to its longitudinal extent, resulting in a substantially tubular shape. The distal end of the liner may also be designed to be open, so that there is no closed container with a proximal opening, but a tube open on both sides with a corresponding inner contour.

Claims

claims

A prosthetic liner for forming an interface between a prosthesis shaft (5) and a stump to be received in the prosthesis shaft (5), the prosthetic liner (1) has a proximal region (2) with a proximal end (21) and a distal region (3) with a distal end (31) and is provided with a closed cross-section with a proximal opening (22) for insertion of the stump in the prosthetic liner (1), characterized in that the inner contour at least on a lateral side (19) of the prosthetic liner (1) distal to proximal in the proximal region (2) has a greater slope than in the distal region (3).

2. prosthetic liner according to claim, characterized in that the distal region (3) has a conical or parabolic inner and / or outer contour.

3. prosthetic liner according to claim 1 or 2, characterized in that the proximal region (2) has a cylindrical or parabolic-like curved inner contour.

4. prosthetic liner according to one of the preceding claims, characterized in that the distal region (3) seen from the distal end (31) extends over 30% up to 75% of the total length of the prosthetic liner (1).

5. prosthesis liner according to one of the preceding claims, characterized in that it is at least in the distal region (2) of multilayer construction and an inner layer (12) of one of an outer layer (11) different material, in particular of silicone having.

6. prosthetic liner according to one of the preceding claims, characterized in that a textile reinforcement (4) in the prosthetic liner (1) is provided.

7. prosthetic liner according to one of the preceding claims, characterized in that from the distal end (31) to the proximal end (21) a discontinuous change in slope is present.

8. prosthesis liner according to one of the preceding claims, characterized in that it is formed closed at the distal end (31).

9. prosthetic liner according to one of the preceding claims, characterized in that the prosthetic liner (1) on the medial side (18) is shorter than on the lateral side (19).

10. prosthetic liner according to one of the preceding claims, characterized in that the prosthetic liner (1) is formed rotationally symmetrical in the longitudinal direction.

11. prosthetic liner according to one of the preceding claims, characterized in that in the distal region (2) at least on the lateral side (19) a padding (20) is present.